The control of fly larval infestation is important in agricultural in order to avoid the illnesses and economic losses associated with such insect pest infestation. A method of controlling fly larval by direct application to the larval breeding medium is widely known in the industry. The method involves such direct utilization of the compound, N[[4-chlorophenyl)amino]carbonyl]-2,6-difluorobenzamide, sold under the tradename of DIMILIN.RTM. insecticide, a registered trademark of Duphar BV of Amsterdam, Holland (hereinafter referred to as diflubenzuron, the generally recognized generic chemical name).
Due to the effectiveness of diflubenzuron when used against fly larvae, the search for a more beneficial manner to control such fly larvae has spurred and continues to spur new research efforts. One attractive method for fly larvae control is to utilize diflubenzuron in feeds for controlling fly larvae in excreted feces. This method is commonly referred to as feed-through application. For instance diflubenzuron at levels of 0.5 to 1.0 mg/kg animal body weight, has been mixed directly into the feed of calves and dairy cattle and has shown effective control of house fly and face fly larval in the feces (R. W. Baker et al, J. Georgia Entomol. Soc., 11 (1976) 1: 67-71 and R. W. Miller, J. Economic Entomol. 67 (1974) 5: 697).
In addition to this direct feed addition method, diflubenzuron has been encapsulated and tested for insecticidal activity, F. W. Knapp et al., Symp. Int. Meeting Controlled Release Soc. (Academic Press, 1980), as well as being applied in mineral blocks and delivered in a sustained-release bolus form (U.S. Pat. No. 4,166,107, issued to J. A. Miller et al on AUg. 28, 1979).